Reland "packages.proto: Add NeedsChromeSource endpoint.""

This reverts commit 593d766e61c787a7b45b6614da2bed7922ce5581
(Relands 7e9f617ada9710f0f68a888023f7028c9913adfe).

BUG=chromium:1086714
TEST=generate.sh

Cq-Depend: chromium:2683218
Change-Id: I74b99f11a8c4028bab6e4fef304eed6ef8842a72
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/infra/proto/+/2683207
Reviewed-by: Sean McAllister <smcallis@google.com>
Commit-Queue: LaMont Jones <lamontjones@chromium.org>
3 files changed